Optical illusion portraits in 1800's Australia used trick photography

Even today this image looks pretty darn trippy, but imagine how it would have been received in the 1800s. Using trick photography the photographers at South Australia's Hammer and Co. created this image of a woman's head and shoulders mounted on a stone plinth. The photographic studio was founded by William Hammer in 1882, capturing portraits of generations of South Australians. Hammer died in 1919, but the business continued on until 1984. [State Library of South Australia]